This invention relates generally to a laminated plastic material having air-tight cell or cells and useful for cushioning or shock absorbing applications.
Cushioning material such as a cushioning sheet composed of two laminated films and having a plurality of air-tight cells therebetween is well known and is widely used in, for example, packaging products or padding furnitures. Conventional cushioning materials, which are generally formed of a polyolefin such as a low density polyethylene, have a problem because they are relatively poor gas barrier materials. Thus, for example, when such cushioning materials are used under pressurized conditions, air entrapped in the cells is gradually forced out of the cells so that the cushioning property is deteriorated. This is especially so when the pressed cushioning materials are also subjected to a great change of temperature.